-
Article
Cygnus X-3 revealed as a Galactic ultraluminous X-ray source by IXPE
The accretion of matter by compact objects can be inhibited by radiation pressure if the luminosity exceeds a critical value known as the Eddington limit. The discovery of ultraluminous X-ray sources has shown...
-
Article
Complex rotational dynamics of the neutron star in Hercules X-1 revealed by X-ray polarization
In an accreting X-ray pulsar, a neutron star accretes matter from a companion star through an accretion disk. The magnetic field of the rotating neutron star disrupts the inner edge of the disk, funnelling the...
-
Reference Work Entry In depth
Introduction to Photoelectric X-ray Polarimeters
X-ray astronomy has been impaired by the lack of access to the unique information contained in the polarization of X-rays emitted by celestial sources, due largely to the insufficient sensitivity of available ...
-
Reference Work Entry In depth
IXPE: The Imaging X-ray Polarimetry Explorer
Launched on December 9, 2021, the Imaging X-ray Polarimetry Explorer (IXPE) is a NASA Small Explorer Mission designed to open up a new window of investigation – x-ray polarimetry. The IXPE observatory contains...
-
Reference Work Entry In depth
Gas Pixel Detectors for Photoelectric X-ray Astronomical Polarimetry
The gas pixel detector is a true 2D imaging device that has been designed and built to image the projection of the photoelectron track, produced by an X-ray photon, onto a pixelated sensitive plane. It is a se...
-
Article
Discovery of X-ray polarization angle rotation in the jet from blazar Mrk 421
The magnetic-field conditions in astrophysical relativistic jets can be probed by multiwavelength polarimetry, which has been recently extended to X-rays. For example, one can track how the magnetic field chan...
-
Article
X-ray polarization evidence for a 200-year-old flare of Sgr A*
The centre of the Milky Way Galaxy hosts a black hole with a solar mass of about 4 million (Sagittarius A* (Sgr A)) that is very quiescent at present with a luminosity many orders of magnitude below those of acti...
-
Article
A space-borne X-ray imaging polarimeter
A year of science from the Imaging X-ray Polarimetry Explorer has brought results that are stimulating a re-examination of theoretical models of astrophysical sources.
-
Article
Simultaneous space and phase resolved X-ray polarimetry of the Crab pulsar and nebula
The Crab pulsar and its nebula are among the most studied astrophysical systems, and constitute one of the most promising environments where high-energy processes and particle acceleration can be investigated....
-
Article
Determination of X-ray pulsar geometry with IXPE polarimetry
Using observations of X-ray pulsar Hercules X-1 by the Imaging X-ray Polarimetry Explorer we report a highly significant (>17σ) detection of the polarization signal from an accreting neutron star. The observed de...
-
Article
Vela pulsar wind nebula X-rays are polarized to near the synchrotron limit
Pulsar wind nebulae are formed when outflows of relativistic electrons and positrons hit the surrounding supernova remnant or interstellar medium at a shock front. The Vela pulsar wind nebula is powered by a y...
-
Article
Open AccessPolarized blazar X-rays imply particle acceleration in shocks
Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are ...
-
Living Reference Work Entry In depth
Introduction to Photoelectric X-Ray Polarimeters
X-ray astronomy has been impaired by the lack of access to the unique information contained in the polarization of X-rays emitted by celestial sources, due largely to the insufficient sensitivity of available ...
-
Living Reference Work Entry In depth
IXPE: The Imaging X-Ray Polarimetry Explorer
Launched on December 9, 2021, the Imaging X-ray Polarimetry Explorer (IXPE) is a NASA Small Explorer Mission designed to open up a new window of investigation – x-ray polarimetry. The IXPE observatory contains...
-
Living Reference Work Entry In depth
Gas Pixel Detectors for Photoelectric X-ray Astronomical Polarimetry
The gas pixel detector is a true 2D imaging device that has been designed and built to image the projection of the photoelectron track, produced by an X-ray photon, onto a pixelated sensitive plane. It is a se...
-
Article
Open AccessA polarized view of the hot and violent universe
X-ray polarimetry has long been considered the ‘holy grail’ of X-ray astronomy. Fortunately, after a silence of more than 40 years, the field is now rejuvenating. In fact, an X-ray polarimeter onboard a Cube-s...
-
Article
Author Correction: Re-detection and a possible time variation of soft X-ray polarization from the Crab
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
-
Article
Re-detection and a possible time variation of soft X-ray polarization from the Crab
The Crab nebula is so far the only celestial object with a statistically significant detection in soft X-ray polarimetry1–4, a window that has not been explored in astronomy since the 1970s. However, soft X-ray p...
-
Article
PolarLight: a CubeSat X-ray polarimeter based on the gas pixel detector
The gas pixel detector (GPD) is designed and developed for high-sensitivity astronomical X-ray polarimetry, which is a new window about to open in a few years. Due to the small mass, low power, and compact geo...
-
Chapter
X-Ray Polarimetry (Instrument/Techniques/Calibration)
X-ray polarimetry is an “old” field in Astronomy which is rapidly evolving, thanks to the development of sensitive instrumentation and to mission proposals arrived at a various stages of implementation. It was...
